To make new services in the vehicle possible, communication among the control units located in different bus segments is indispensable. Such communication may take place only if the different bus segments are connected to one another via one or more gateway units. A gateway unit connecting two bus segments has the function of relaying messages received on one bus segment to another bus segment (routing). The complexity of such a gateway unit increases with the number of bus segments to be connected. When designing the network connection architecture of a vehicle, an attempt is made to find an optimum for the characteristics of tolerable delay for message routing, error tolerance, flexibility, expansibility, and cost. Depending on the application, central gateway units having a star architecture or a plurality of gateway units which may be connected by a backbone bus, for example, are used. The gateway units via which different buses are connected are configured (for example, via tables). As a result, pure message routing to another segment does not require a change in the software. However, if the type and number of connected bus segments change, major changes are needed, in which not only the existing configuration tables must be adapted, but the entire software must be rewritten to meet the new requirements. The complexity of the central configuration and the routing software thus increases significantly with the number of connected bus segments.